The story of the U.S. men’s national team’s progress through the semifinal round of CONCACAF’s lengthy World Cup qualifying slog might have been far different without the contributions of several players who weren’t expected to play a part.

Ignored by coach Jurgen Klinsmann during the first nine months of his tenure, forward Herculez Gomez returned to the fold last May, started all six qualifiers and scored the only goal in a 1-0 win over Jamaica in early September.

Eddie Johnson returned from soccer oblivion, re-established himself with the Seattle Sounders and then was entrusted with a starting role in the October qualifier at Antigua and Barbuda. He scored both goals in a 2-1 victory, including the 90th-minute clincher.

Graham Zusi (Sporting Kansas City) and Geoff Cameron (then with the Houston Dynamo, now at Stoke City) boasted one U.S. cap combined when they were invited to Klinsmann’s first January camp, where they excelled. Cameron then started the semifinal round’s final four qualifiers. Zusi was in the first 11 for the climactic three, each of which the Americans won.

“If guys in MLS don’t see (players like Zusi and Cameron) getting a look and making an impact and seeing that as an opportunity, I don’t know what they’re thinking,” Gomez said following his star turn vs. Jamaica. “I think Jurgen’s shown that everybody has a chance to play for this team as long as you can be an integral part of it, do your part and bring that effort.”

Fast-forward to Tuesday night, when the newest crop of January campers will strive to make their national team case as the U.S. hosts Canada in an exhibition at BBVA Compass Stadium in Houston (9 p.m. ET, ESPN2).

In a year that eventually will be remembered for the Hexagonal marathon and this summer’s CONCACAF Gold Cup, a January friendly against a struggling young Canadian side should be a footnote. But it also might be a significant stepping stone for players Klinsmann will rely on down the road.

“The last three weeks showed us that we maybe have a deeper pool than we thought,” Klinsmann told reporters over the weekend. “We have a lot of good players coming through, and their job is to challenge whoever’s in front of them. It was great to see there’s a next generation of players that are eager and hungry to get to the next level."

Those players will get 90 minutes to prove their worth, and some may be named to the squad that heads to Honduras for the Hexagonal opener on Feb. 6.

“There’s a lot at stake for the players in this Canada game,” Klinsmann said.

Among the 23 men eligible to take the field Tuesday, seven have never played for the senior U.S. side and only five have more than 10 caps. Yet Klinsmann’s history suggests that each of them has a legitimate opportunity to climb up his depth chart—even those who lack experience or who feared their international careers had ended. At a minimum, the coach has them believing the possibility is there.

“He puts everybody on a level playing field. I can tell you that,” said Brad Davis, the veteran Houston Dynamo midfielder who hasn’t played for the U.S. in three years. “It doesn’t matter what your name is or how long you’ve been around. It’s, ‘What can you do from today and what can you do for me tomorrow?’ It’s about consistency. It doesn’t matter if you’re paying in Europe or MLS.”

In the months following Klinsmann’s July 2011 appointment, many thought the German World Cup winner favored players who worked abroad. He engineered European loans and training stints for MLS players and stressed the importance of competing at the highest level. But it’s clear now that his obsession with improvement applies to everyone, not just those making their living in the U.S. For those who weren’t listening over the past year, Klinsmann hammered that point home last week when he told The Wall Street Journalthat U.S. star Clint Dempsey, who set a record in 2011-12 for goals scored by an American abroad, “hasn’t made (expletive) playing for Fulham.

“Yeah, so?” Klinsmann asked. “Show me you can play for a (UEFA) Champions League team, and then you start on a Champions League team. There is always another level. If you one day reach the highest level then you've got to confirm it, every year."

Dempsey now plays for Fulham’s London rival, Tottenham Hotspur, which is in the hunt for one of England’s four Champions League berths.

Rather than leaving MLS players feeling like they’re too far removed from soccer’s spotlight, Klinsmann’s refusal to let anyone rest on their laurels has them feeling energized.

“That’s kind of refreshing. I think in the past when I’ve come into January camps, I don’t think that was necessarily the mentality of the coach. I don’t think MLS guys were looked at as the same level of the European players,” said Davis, who’s arguably been the league’s top left midfielder over the past three years. “Now you come in and you make a difference, do your job, you’re going to stick around. You can definitely say he’s had different names in camps and given guys different opportunities, for sure. This just happens to be my opportunity.”

One of those new names is Justin Morrow, the San Jose Earthquakes left back who’s in camp with the U.S. for the first time. The 25-year-old Notre Dame product said his three weeks with Klinsmann in California have been demanding.

“The most glaring thing about it is how mentally challenging it is,” he said. “Everyone’s bringing it, and it’s not just at practice. It’s every single thing. The way you prepare for practice. The way you carry yourself. When you walk into breakfast and you’re yawning, is he reading into that? You’re always thinking about it.”

But Morrow stressed that camping with Klinsmann has been far from uncomfortable.

“He creates a good environment for us to express ourselves, but he’s all about us being complete footballers and professionals and this isn’t only our job. We need to take it as our whole life,” Morrow said. “He’s always looking for more and he’s not against MLS or players who play domestically. It’s whatever level you’re at, he’s looking for you to take it to the next level or at least stay consistent. I was an All-Star this year. It would send a huge message to him if I’m an All-Star again next year.”

Those who take the field on Tuesday and perform well will be sending a message as well. Klinsmann is waiting to be convinced.

“It’s a huge year for U.S. soccer and you have to make the most of each opportunity you get. It doesn’t matter if it’s a friendly against Canada,” Davis said. “This is a good opportunity for me to hopefully push myself toward that qualifier in Honduras, and if that opportunity comes I’ll take it as just one more opportunity. It’s all about, ‘Can you be consistent? Can you maintain a high level?’ If you can do that, you’ll get another shot.”